In an array substrate of a GOA (Gate On Array) mode, a gate driving circuit for driving gate lines to generate scanning signals (i.e., output turn-on signals in turns) is directly provided on a substrate base of the array substrate, the gate driving circuit comprises a plurality of cascaded shift registers, an output terminal of each of the shift registers is connected to one of the gate lines, by providing several simple control signals to the gate driving circuit, the shift registers sequentially output turn-on signals to the gate lines.
Generally, there is a fixed scanning direction for the gate lines in the array substrate, for example, a forward (from top to bottom) scanning direction or a backward (from bottom to top) scanning direction. However, in some cases (e.g., when a multi-screen display is performed), it may require to achieve a dual scanning function, that is, require the array substrate to either scan forward or scan backward.
In order to achieve the dual scanning function, the gate driving circuit must be changed to increase the number of devices therein and simultaneously increase the number of control signals (i.e., increase the number of control signal lines) required by the gate driving circuit, resulting in a complex structure of the gate driving circuit of prior art for achieving the dual scanning function and a large number of control signals required by the gate driving circuit.